Estimation of Genetic and Phenotypic Parameters for Growth Traits in a Clonal Seed Orchard of Pinus kesiya in Malawi

Genetic and phenotypic parameters for height, diameter at breast height (dbh), and volume were estimated for Pinus kesiya Royle ex Gordon clonal seed orchard in Malawi using an ASReml program, fitting an individual tree model. The data were from 88 clones assessed at 18, 23, 30, 35, and 40 years of age. Heritability estimates for height, dbh, and volume were moderate to high ranging from 0.19 to 0.54, from 0.14 to 0.53, and from 0.20 to 0.59, respectively, suggesting a strong genetic control of the traits at the individual level, among families, and within families. The genetic and phenotypic correlations between the growth traits were significantly high and ranged from 0.69 to 0.97 and from 0.60 to 0.95, respectively. This suggests the possibility of indirect selection in trait with direct selection in another trait. The predicted genetic gains showed that the optimal rotational age of the Pinus kesiya clonal seed orchard is 30 years; therefore, it is recommended to establish a new Pinus kesiya clonal seed orchard. However, selective harvest of clones with high breeding values in the old seed orchard should be considered so that the best parents in the old orchard can continue to contribute until the new orchard is well established.

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Management strategies of Eremanthus erythropappus (DC.) MacLeish under different initial spacing

Ciência e Agrotecnologia ◽

10.1590/1413-70542016403042715 ◽

2016 ◽

Vol 40 (3) ◽

pp. 298-304 ◽

Cited By ~ 5

Author(s):

José Roberto Soares Scolforo ◽

Thiza Falqueto Altoe ◽

Henrique Ferraco Scolforo ◽

Jose Marcio de Mello ◽

Charles Plinio Castro e Silva ◽

...

Keyword(s):

Management Strategies ◽

Tree Model ◽

Individual Tree ◽

Crown Area ◽

High Durability ◽

Spacing Variation ◽

Generating Tree ◽

Initial Spacing ◽

Individual Tree Model ◽

The Individual

ABSTRACT Eremanthus erythropappus, commonly known as candeia, is an income-generating tree native to Brazil. This is due to the high durability of its wood and its essential oil containing the active component alpha bisabolol. Despite this economic potential, until the early 2000's no studies existed to explore the sustainable management in areas in which the species naturally occurs or for establishing commercial plantations. This study proposes new management strategies based on an individual tree model, and evaluates the growth behavior of candeia trees planted in different spacing. The experiment was installed in March 2002, in Carrancas municipality, Minas Gerais state, Brazil. The experimental area was divided into 4 blocks with 4 different spacings as treatments. The individual model used to propose the best management system uses development of crown area as a function of DBH. The results showed that candeia trees were sensitive to initial spacing variation. With increased initial spacing, candeia trees reached competition later, as demonstrated by crown area development. Thus, candeia trees planted at a wider spacing maintain a desirable growth rate without need for thinning for a longer time, compared to trees planted at narrower spacing. The fitted individual tree model presented in this study showed consistent results and flexibility, providing alternatives for different management strategies. The best growth response was obtained for planting densities greater than 3.75 m² per tree, which corresponds to a spacing of 1.5 x 2.5 m.

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Genetic Control of Growth Traits in Shortleaf Pine in Missouri

Southern Journal of Applied Forestry ◽

10.1093/sjaf/29.4.200 ◽

2005 ◽

Vol 29 (4) ◽

pp. 200-204 ◽

Cited By ~ 2

Author(s):

David P. Gwaze ◽

Ross Melick ◽

Charly Studyvin ◽

Mark Coggeshall

Keyword(s):

Growth Traits ◽

Genetic Correlations ◽

Selection Criterion ◽

Seed Orchard ◽

Direct Selection ◽

Pinus Echinata ◽

Shortleaf Pine ◽

Individual Tree ◽

High Heritability ◽

Heritability Estimates

Abstract Genetic parameters for height (HT), diameter (diameter at breast height [dbh]), and volume for a shortleaf pine (Pinus echinata Mill.) population in Missouri were estimated from a single progeny test comprising 44 half-sibling families assessed at 3, 5, 7, 10, and 17 years. Individual tree heritability estimates for growth traits at age 10 years and younger were high (0.30–0.43), and those at age 17 years were low (0.11–0.24). Heritability estimates for dbh were lower than those for HT. Family mean heritability estimates were moderate to high (0.32–0.66). Genetic correlations were higher than their phenotypic counterparts for all growth traits. Age-age genetic correlations for growth traits were moderate to high (0.68–0.98), indicating opportunity for early selection. Genetic correlations between different growth traits were high (0.81–1.00). Indirect selection on age 5- or 7-year HTs may be expected to produce over 25% more volume at 17 years compared with direct selection for volume at age 17 years. Efficiencies of selection suggest that early HT is a better selection criterion for volume at older ages than dbh because of the high heritability at young ages and strong juvenile-mature genetic correlations. Genetic gain in an unrogued seed orchard was predicted to be 6.7 and 27.2% for 10- and 17-year volume, respectively. These results suggest that growth traits in shortleaf pine in Missouri have high genetic variation, and genetic improvement was effective. South. J. Appl. For. 29(4):200–204.

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Performance and comparison of stand growth models based on individual tree and diameter-class growth

Canadian Journal of Forest Research ◽

10.1139/x79-040 ◽

1979 ◽

Vol 9 (2) ◽

pp. 231-244 ◽

Cited By ~ 50

Author(s):

Alan R. Ek ◽

Robert A. Monserud

Keyword(s):

Growth Model ◽

Growth Models ◽

Stand Density ◽

Diameter Class ◽

Tree Model ◽

Individual Tree ◽

Clear Cut ◽

Individual Tree Model ◽

The Individual ◽

Stand Conditions

A distance-dependent individual tree based growth model (FOREST) was compared with a diameter-class growth model (SHAF) for describing changes in stand density and structure. Projections of Lake States' northern hardwood stand development were made by each model for 5–26 years over a range of stand conditions and harvest treatments. Results from numerous performance tests and comparisons of actual and predicted diameter distributions, basal areas, and numbers of trees, indicate the individual tree model was considerably more sensitive to harvest treatments and reproduction response than the diameter-class model. Conversely, the latter was much less expensive to operate. Prediction of species and individual tree growth with the individual tree model appeared to provide sensitivity nearly equal to that observed for predictions of the stand as a whole. Long-term projections (120 years) for reserve (no cut) and clear-cut stand conditions further suggest the potential and limitations of the models for management analyses.

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A Comparison of Loblolly Pine Plantation Growth and Yield Models for Inventory Updating

Southern Journal of Applied Forestry ◽

10.1093/sjaf/20.1.15 ◽

1996 ◽

Vol 20 (1) ◽

pp. 15-22 ◽

Cited By ~ 7

Author(s):

James S. Shortt ◽

Harold E. Burkhart

Keyword(s):

Loblolly Pine ◽

Growth And Yield ◽

Diameter Distribution ◽

Distribution Models ◽

Tree Model ◽

Individual Tree ◽

Parameter Recovery ◽

Individual Tree Model ◽

The Individual ◽

Growth And Yield Models

Abstract Four different loblolly pine growth and yield models were evaluated for the purpose of updating forest inventory data. The types of growth and yield models examined were: a whole stand, a diameter distribution-parameter prediction, a diameter distribution-parameter recovery, and an individual tree model. Three different approaches were used to create fitting and validation data sets from permanent plot remeasurement data; each of the four growth and yield models was evaluated at varying projection periods. The periods used were 0, 3, 6, and 9 yr. Evaluations were based solely on the capability of each model to predict merchantable volume. In terms of root mean square error of prediction, the individual tree and whole stand models performed better than the diameter distribution models. At shorter projection periods, the individual tree model performed better than the whole stand model, but the whole stand approach was superior at the 9 yr period. Of the diameter distribution models, the parameter recovery model performed better for shorter periods than the parameter prediction model, but this difference diminished with longer periods. South. J. Appl. For. 20(1):15-22.

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Using disaggregation to link individual-tree and whole-stand growth models

Canadian Journal of Forest Research ◽

10.1139/x05-284 ◽

2006 ◽

Vol 36 (4) ◽

pp. 953-960 ◽

Cited By ~ 22

Author(s):

Jianhua Qin ◽

Quang V Cao

Keyword(s):

Loblolly Pine ◽

Growth Models ◽

Basal Area ◽

Tree Model ◽

Individual Tree ◽

Stand Growth ◽

Individual Tree Model ◽

Stand Attributes ◽

Pinus Taeda L ◽

The Individual

Data from 200 plots randomly selected from the Southwide Pine Seed Source Study of loblolly pine (Pinus taeda L.) were used to fit whole-stand and individual-tree equations. Another 100 plots, also randomly selected, were used for validation. Outputs from the individual-tree model were then adjusted to match observed stand attributes (number of trees, basal area, and volume per hectare) by four disaggregation methods: proportional yield, proportional growth, constrained least squares, and coefficient adjustment. The first three are existing methods, and the fourth is new. The four methods produced similar results, and the coefficient adjustment was then selected as the method to disaggregate predicted stand growth among trees in the tree list. Results showed that, compared to the unadjusted individual tree model, the adjusted tree model performed much better in predicting stand attributes, while providing comparable predictions of tree diameter, height, and survival probability. The proposed approach showed promise in the ongoing effort to link growth models having different resolutions.

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Incorporating competition factors in a mixed-effect model with random effects of site quality for individual tree above-ground biomass growth of Pinus kesiya var. langbianensis

New Zealand Journal of Forestry Science ◽

10.33494/nzjfs492019x27x ◽

2019 ◽

Vol 49 ◽

Cited By ~ 2

Author(s):

Mingchuan Nong ◽

Yan Leng ◽

Hui Xu ◽

Chao Li ◽

Guanglong Ou

Keyword(s):

Site Quality ◽

Biomass Estimation ◽

Mixed Effect Model ◽

Above Ground Biomass ◽

Mixed Effect ◽

Individual Tree ◽

Pinus Kesiya ◽

Effect Model ◽

The Individual ◽

Better Than

Background: Accurate biomass estimation has critical effects on quantifying carbon stocks and sequestration rates, and above-ground biomass (AGB) growth models are a key component of tree biomass estimation. The study objective was to develop a growth model for AGB of an individual tree by combining competition factors and site quality using a mixed-effect model. Methods: The AGB of 128 sampling trees was investigated for Simao pine (Pinus kesiya var. langbianensis) at three typical sites near Pu’er City of Yunnan Province, China. Richards’ Equation was used for the basic growth model (BM) of the AGB, and a mixed-effect model with random effect of site quality (MEM) based on BM and a mixed-effect model with fixed effect of competition factors (MEMC) based on MEM were built using S-plus. Results: Both mixed-effect models are significantly better than the basic model in fitting and predicting the individual tree AGB growth for Simao pine, but the MEM is better than the MEMC. Moreover, the mixed-effect model with competition factors and site quality is the optimal estimation model due to its highest prediction precision (P=86.08%) as well as the lowest absolute average relative error (RMA=54.34%) and average relative error (EE =6.45%). Conclusion: A model including site quality and competition factors can be used to improve the tree AGB growth estimation for the individual tree AGB growth of Simao pine.

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Genetic Variation and Realized Genetic Gain From Black Pine Tree Improvement

Silvae Genetica ◽

10.1515/sg-2005-0015 ◽

2005 ◽

Vol 54 (1-6) ◽

pp. 96-104 ◽

Cited By ~ 4

Author(s):

D. Matziris

Keyword(s):

Genetic Gain ◽

Seed Orchard ◽

Pinus Nigra ◽

Growth Characteristics ◽

Progeny Testing ◽

Black Pine ◽

Narrow Sense Heritability ◽

Individual Tree ◽

Clonal Seed Orchard ◽

Pine Tree

Summary In 1978 a 10 ha clonal seed orchard of black pine (Pinus nigra Arnold) was established in the area of Koumani in the western part of Peleponnesos, Greece. The orchard comprises 52 clones derived from intensively selected plus trees in the natural forest of black pine of Peloponnesos. In 1991 three open pollinated progeny tests were established in Peloponnesos, proximal to the villages of Raches, Vlachokerasia and Vamvakou. Seedlings from 52 families including a commercial check (CC) were planted in each one of the three locations. Assessments were made when the trees were 4, 7 and 9 years respectively, with the following results. The variation among families for growth characteristics were highly significant in all locations examined. In the combined analyses of variance over the three locations, significant differences among families were also detected, while the family x location interaction effect was not significant. This indicates that the seed produced from the seed orchard can be freely used over the environments of the three experimental plantings, which are representative of the broad area of Peloponnesos. Narrow sense heritability estimates on individual tree basis (h2) were variable depending on the characteristic, age of assessment and the location of the experimental plantings. The estimates of h2 in Vlachokerasia for height (HT) were 0.21, 0.40 and 0.43 at the ages of 4, 7 and 9 years respectively. In Raches the corresponding h2 values for HT were nearly the same in all ages (0.29, 0.28 and 0.31 at 4, 7 and 9 years respectively) and stable but little higher (0.31, 0.28 and 0.31) at the Vamvakou experimental planting. The heritability values for HT estimated over the three location, were relatively low (0.25, 0.23 and 0.19) at the ages 4, 7 and 9 years respectively. Realized genetic gains were calculated for growth characteristics at the age of 9 years, by comparing the performance of the improved (selected) materials to unimproved materials (CC). For the first stage of selection (selection made in natural stands) gain of 6.0% for HT, 8.0% for diameter breast height (DBH) and 24% for volume were estimated. When 20% of the clones, with the lower breeding values are removed from the seed orchard (genetic thinning), an additional gain of 2% for HT, 3% for DBH and 8% for volume over the unrogued seed orchard is resulted. Thus, the total genetic gain from the genetically tested, first generation seed orchard of black pine at Koumani is estimated as 8% for HT, 11% for DBH and 32% for volume. These results indicate that improvement of black pine by selection, establishment of seed orchard and progeny testing the clones, is a very promising profitable operation.

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Spatial and competition models increase the progeny testing efficiency of Japanese larch

Canadian Journal of Forest Research ◽

10.1139/cjfr-2020-0007 ◽

2020 ◽

Vol 50 (12) ◽

pp. 1373-1382 ◽

Cited By ~ 1

Author(s):

Leiming Dong ◽

Yunhui Xie ◽

Harry X. Wu ◽

Xiaomei Sun

Keyword(s):

Growth Traits ◽

Japanese Larch ◽

Larix Kaempferi ◽

Progeny Testing ◽

Forward Selection ◽

Individual Tree ◽

Breeding Values ◽

The Individual ◽

Residual Variances ◽

Model C

The main purpose of this study was to examine spatial and competition effects on estimates of genetic parameters, as well as on selection options for growth traits, including height (H), diameter at breast height (DBH), and volume (V), in a progeny test of Japanese larch (Larix kaempferi (Lam.) Carrière) at age 20 years. We compared performances among the individual-tree additive genetic base model (B) with design factors only, the spatial effect model (AR1), the competition model (C), and the combined competition and spatial model (CS). We found that spatial heterogeneity had significant effects on growth traits and that plot variance decreased by more than 80% in the AR1 model relative to the B model. Competition had significant effects on DBH and V but a smaller effect on H. In the C model, direct additive genetic variances ([Formula: see text]) for DBH and V increased by 205% and 93%, respectively, whereas residual variances ([Formula: see text]) decreased by 8% and 6%, respectively. In the CS model, the correlations between direct and competitive genetic effects were 0.83, −0.97, and −0.98 for H, DBH, and V, respectively. Competition significantly affected the forward selection. The proportions of selected elite trees were only 39% and 25% common between the B and CS models for DBH and V, respectively, when selection intensity was 5%. For breeding selection, depending on thinning regimes planned, trees of high additive breeding values but low competitive breeding values are preferable for plantation.

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Projection of a diameter distribution through time

Canadian Journal of Forest Research ◽

10.1139/x06-216 ◽

2007 ◽

Vol 37 (1) ◽

pp. 188-194 ◽

Cited By ~ 10

Author(s):

Jianhua Qin ◽

Quang V Cao ◽

David C Blouin

Keyword(s):

Projection Method ◽

Loblolly Pine ◽

Growth Period ◽

Distribution Model ◽

Diameter Distribution ◽

Tree Model ◽

Individual Tree ◽

Recovery Method ◽

Tree Survival ◽

Individual Tree Model

Three approaches to characterizing the diameter distribution of a future stand are presented. The first approach is the "parameter-recovery" method, which links a whole-stand model to a diameter-distribution model. The next two approaches provide linkages between an individual-tree model and a diameter-distribution model. Tree-survival and diameter-growth equations were applied to the tree list (the "tree-projection" method) or to the diameter distribution (the "distribution-projection" method) at the beginning of the growth period. A numerical example of Weibull distributions that characterized diameter data from the Southwide Seed Source Study of loblolly pine (Pinus taeda L.) is presented. All three methods produced similar results in terms of Reynolds et al.'s (1988) error indices, whereas the distribution-projection method outperformed the other two methods in predicting total and merchantable volumes per hectare. This study demonstrated that the diameter-distribution model could be linked to either a whole-stand model or an individual-tree model with comparable success.

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